Mine



March 31,1925

. 1,531,550 J. B. GLEN NON MINE Fi-led llay 27, 1922 s Shets-Sheet 1 March 31. 1925. 1,531,550

J. B. GLENNON I MINE Filed May 27, 1922 3 Sheets-Sheet 2 Patented Mar. 31, 1925.

UNITED STATES JAMES B. GLENNON, 0'! WASHINGTON, DISTRICT, OF COLUMBIA, ASSIGNOR TO' THE 1,53 ,550 PATENT OFFICE.

GOVERNMENT OF THE UNITED STATES.

MINE.

Application filed May 27, 1922. Serial 2N0. 564,229.

To all whom it may concern:

Be it known that I, JAMES B. GLENNON, a citizen of the United States, residing at Washington, District of Columbia, have invented new and useful Improvements in Mines, of which the following isa specification.

This invention. relates to improvements in submarine mines and more particularly to mines adapted to be fired by contact with a passing ship although many features of the invention are applicable to what are called placement mines for .harbor defense adapted to be fired from a shore station by observation;

One of the objects of the present inven tion is to provide an improved contact mine which will be reliable and eflicient in use and operation.

A further object is to provide amine of the above character which will fire automatically on contact or may be fired from observation.

A further object is to provide a mine adapted to explode adjacent the .most vulnerable part of a ship, that is, near the midship section and beneath the bottom thereof.

A. further object is to provide a mine which will not be thrown aside by paravanes or other forms. of sweep.

A further object is to provide amine suitable for use in a barrage against submarines and yet fully effective against surface vessels.

A further object. is to provide a nonsweepable controlled mine.

Other objects will be in .part obvious and in part hereinafter pointed out in connection with the accompanying sheets of drawings illustratin twoof various possible embodiments of t e invention.

In these drawings wherein like reference characters denote corresponding parts,

Figure 1 is a diagrammatic view illustrating a portion of the mine field at the entrance of a harbor. 4

Figure 2 is a diagrammatic view showing the wiring circuits.

Figure 3 isa detail, sectional view through a portion of the mine casing.

Figure dis a detail sectional view of a modified form of circuit closing device.

Referring to the accompanying drawings in detail and more particularly to Figure 1,

5 denotes the buoys or floats carried at the upper end of antenna 6, the opposite end of which is secured to the mine casing 7 which in turn is provided with an anchor line 8 connected with a mine anchor 11.

If either of the parts 5, 6 or '7 is engaged by a passing ship or the paravane cables carried thereby in case the ship is provided with suchdefensive means, mechamsm Wlll be actuated to release the mine casing 7 from the upper end of the anchor line 8 and by reason of the natural buoyancy of the mine casing 7 it will rise and be automatically fired at a predetermined depth beneath the midship section of the passing boat. This release of the mine from its anchor is accomplished by substantially the same mechanism employed in the mines used in forming the North Sea barrage during the late war and may briefly be stated to consist in the utilization of the current generated by the ship as one electrode, a copper plate carried by the mine as the other electrode and the sea water in which both ship and. mine are immersed as the electrolyte. Thus when the ship or paravane 9 contacts with any one of the parts 5, 6 or 7 the circuit is completed to electrically release the mine from its anchor as shown in the middle of Figure 1.

At the right of Figure 1 there is shown a slight modification of the present invention but it operates upon substantially the same principle. The mines carried in anchors 11 are preferably of a frustro-conical or frustro pyramidal shape in which the mines 7 are seated as indicated. The-mines will be released from their anchors or from an observation station 12 by closing a switch thereby completing circuit which actuates an armature thence the electrically actuated mine' releases mechanism hereinafter described in detail.

Referring now to Figure 3 of the draw-. ings, the mine casing 7 is of general spherical type provided at its upperend with attaching means 15 to which the antennae 6 is connected and at its lower end with attaching means 17 to which the anchor line 8 is connected. Between the parts 17 and 8 is a releasing hook 20 coact-ing with a shackle 21. The releasing hook is provided with the main supporting member 20 and a. latch 22 held in locked position by means of bolt 23 held in inward position by means of a shear pin 24. Within the casing 25 is a primer adapted to be electrically fired by current passing through wire 26 thereby to shoot outthe bolt 23 which releases the latch 22 and disconnects the mine 7 from its anchor line 8.

l/Vi-thin the mine casing'is an actuating mechanism box 30 containing the actuating mechanism and circuit closing devices. A battery 31 is also'provided for furnishing the necessary current,these parts being connected electrically as shown and as will hereinafter be explained in connection with Figure 2. 1

It is, of course, to be understood that the mine casing is filled with any desired high explosive.

In Figure 2 the float 5 and antenna 6 are indicated diagrammatically as well as a copper plate 33 at the top of the mine. hen the parts 5 or 6 are engaged by a passing ship, for example, current is generated to energize a coil 34 to close a pivoted switch 35 between contacts 36 and 37. A pivoted switch38 grounded at 40 is held in this open position by means of hydrostatic pressure exerted upon the collapsible diaphragm 41, the parts being held in this position when the mine is at a depth of more than 35 feet, for example. Suitable safety devicessuch as a soluble washer 42 maintains this circuit open while in storage or while the mine is sinking thereby to eliminate any prema-- ture firing of the mine.

It will thus be seen that when the switch 35 closes the circuit between contacts 36, and 37 the circuit is completed from the ground 40 through switch 35, battery 43, wires 44 and 26 to fire the releasing hook primer 46 within the releasing hook 25.

When the mine is released the mine casing immediately tends to rise towards the surface of the water and on reaching a predetermined depth, say 35 feet, the switch .38 will close the circuit at contact 47 whereby current will flow from the battery 43 through mine detonator 48 and fire the mine.

From numerous tests of actual devices it has been ascertained that the mine case will rise at approximately 11 feet a second. It is, therefore, placed orsunk to a depth of approximately feet from the surface of the water and the floats'placed at about 15 feet below the surface of the water where they may be engaged by a passing vessel having sufficient draft to coact therewith. The floats would probably be engaged by the bow of the vessel or the paravanes attached to the bow. The instant, however, the ship or the paravane leads contact with the floats or the antennae the circuit is completed to fire the releasing hook primer 46 and the mine immediatelystarts toward the surface. ing while the mine is going from its anchored depth to the 35 foot or other det- In the few seconds of time elaps Thus the use of paravanes is made dangerous because all mines which would strike a vessel without paravanes will strike a vessel so fitted. In addition, other mines will be exploded close aboard by the paravane wires.

In Figure 4 there is shown a modified form of circuit closing device for firing the releasing hook primer. By means of this device the utilization of the sea battery principle may be dispensed with and the mine will be fired even if engaged by a wooden ship.

The release of the mine from its anchor cable may be caused not only by contact with mine or mine fittings but by influence magnetic, acoustic or other type now or hereafter developed.

Referring to this figure in detail, 50 denotes one electrode or contact member adapted to be secured to the mine case and thence to one side of a battery while the centrally disposed member 51 insulated therefrom by bushings 52 is connected to the other side of the battery. This pin 51 is provided with a weakened neck 53 carrying a contact disc 54 while the upper end is provided with an eye 55 to which a rope carrying a float may be attached or the float and antenna previously described. \Vhenever this eye, antenna or rope is engaged by a passing ship, its paravanes or other fittings, the weakened neck 53 will be bent to bring the disc 54 in contact with the other terminal 50 thereby completing the circuit through the primer releasing hook whereupon the mine will come to the surface in the manner previously described.

It is thus seen that the present invention provides a reliable and efficient mine particularly adapted to fire at its most effective position with respect to a ship engaging therewith and is well adapted to accomplish,

to release the mine from its anchorage when said contact device is engaged by a passing ship.

2. In a submarine mine, in combination, a mine casing adapted to be anchored well below the mean depth of a passing ship, a contact device carried thereby adapted to be engaged by the ship, means adapted to release the mine from its anchorage and means for automatically firing the mine after being released and when it ap roaches the mean depth of a passing ship w en said contact device is engaged by a passing ship.

3. In a submarine mine, in combination, a mine anchor, mine casings associated therewith, both of said parts being normally positioned well below the mean draft of a passing ship and upwardly extending means adapted to be engaged by a passing ship for releasing said mine casing from its anchor whereb it automatically rises.

4. In a su marine mine, in combination, a mine anchor, mine casings associated therewith, both of said parts being normally positioned well below the mean draft of a passing ship, upwardly extending means 7 adapted to be engaged by a passing ship for releasing said mine casing from its anchor whereby it automatically rises and means whereby the explosive in said mine casing is automatically fired.

5. In a submarine mine, in combination, a mine anchor, mine casings associated therewith, both of said parts being normally positioned well below the mean draft of a passing ship, upwardly extending means adapted to be engaged by a passing ship for releasin said, mine casing from its anchor whereby it automatically rises, and means whereby the explosive in said mine casing is automatically fired .when it rises to a predetermined depth.

6. In a submarine mine, in combination,

a mine anchor, a mine casing carrying an ex I plosive secured thereto, an antenna extending upwardly from said mine casing, means for releasing said mine casing from-its anchor when said antenna is engaged by a passing shi and means carried by the mine casing for bring the charge contained therein after said mine casing has been released from its anchor.

. 7. In a submarine mine, in combination, a mine anchor, a mine casing carrying an explosive secured thereto, upwardly extending means adapted to be engaged by a passing ship for releasing said mine casing from its anchor, means carried by the mine casing for firing the charge contained therein after said mine casin has been released from its anchor, said firing means being automatic in its operation and adapted to take place' when the mine has approached a predetermined depth.

8. In a submarine mine, in combination, a mine anchor, a mine casing carrying an explosive secured thereto, upwardly extending means adapted to be engaged by a passing ship for releasing said mine casing from its anchor, means carried by the mine casing for firing the charge contained therein after said mine casing has been released from its anchor, said firing means being automatic in its operation and adapted to take place when the mine has approached a predetermined depth.

9. In a submarine mine, in combination, a mine anchor of substantially frustro-conical shape, a spherical mine casing partially housed therein and means for re easing the mine from the anchor.

10. In a submarine mine, in combination, a mine anchor of substantially frustro-conical shape, a spherical mine casing partially housed therein, ,means for releasi the mine from the anchor and means carried by the casing adapted to cause said mine to explode after it has been released from its anchor, and a spherical mine case, the lower half of which is housed beneath the upper edge of said anchor thereby to prevent sweeping of said mine.

11. In a submarine mine, in combination, a mine anchor of substantially frustro-conical shape, a spherical mine casing partially housed therein, means for releasing the .mine from the anchor and means carried by the casing adapted to cause said mine to explode after it has been released from its anchor and at a predetermined depth below the surface of the water.

Signed at Washington, District of Columbia, this 15th \day of April, 1922.

J. B. GLENNON. 

